IncreaseBitDepth.hpp

Go to the documentation of this file.

#pragma once
 
#include <AH/Settings/Warnings.hpp>
AH_DIAGNOSTIC_WERROR() // Enable errors on warnings
 
#include <AH/STL/type_traits> // enable_if
#include <limits.h>           // CHAR_BIT
#include <stddef.h>           // size_t
 
BEGIN_AH_NAMESPACE
 
template <size_t Bits_out, size_t Bits_in, class T_out, class T_in>
std::enable_if_t<(Bits_out <= 2 * Bits_in), T_out>
increaseBitDepthImpl(T_in in);
 
template <size_t Bits_out, size_t Bits_in, class T_out, class T_in>
std::enable_if_t<(Bits_out > 2 * Bits_in), T_out>
increaseBitDepthImpl(T_in in) {
    constexpr size_t leftShift = Bits_out - Bits_in;
    return (T_out(in) << leftShift) |
           increaseBitDepthImpl<leftShift, Bits_in, T_out>(in);
}
 
template <size_t Bits_out, size_t Bits_in, class T_out, class T_in>
std::enable_if_t<(Bits_out <= 2 * Bits_in), T_out>
increaseBitDepthImpl(T_in in) {
    constexpr size_t leftShift = Bits_out - Bits_in;
    constexpr size_t rightShift = Bits_in - leftShift;
    return (T_out(in) << leftShift) | (in >> rightShift);
}
 
 
template <size_t Bits_out, size_t Bits_in, class T_out, class T_in>
T_out increaseBitDepth(T_in in) {
    static_assert(Bits_in <= sizeof(T_in) * CHAR_BIT,
                  "Error: Bits_in > bits(T_in)");
    static_assert(Bits_out <= sizeof(T_out) * CHAR_BIT,
                  "Error: Bits_out > bits(T_out)");
    return increaseBitDepthImpl<Bits_out, Bits_in, T_out>(in);
}
 
 
END_AH_NAMESPACE
 
AH_DIAGNOSTIC_POP()